Automatic identification of products has become commonplace. For example, the ubiquitous barcode label, placed on food, clothing, and other objects, is currently the most widespread automatic identification technology that is used to provide merchants, retailers and shippers with information associated with each object or item of merchandise.
Another technology used for automatic identification products is Radio Frequency Identification (RFID). RFID uses labels or “tags” that include electronic components that respond to radio frequency commands and signals to provide identification of each tag wirelessly. Generally, RFID tags and labels comprise an integrated circuit (IC, or chip) attached to an antenna that responds to a reader using radio waves to store and access the information in the chip. Specifically, RFID tags and labels have a combination of antennas and analog and/or digital electronics, which often includes communications electronics, data memory, and control logic.
One of the obstacles to more widespread adoption of RFID technology is that the cost of RFID tags are still relatively high as lower cost components and optimization of economical manufacturing of RFID tags has not been achievable using current production methods. Additionally, as the demand for RFID tags has increased the pressure has also increased for manufacturers to reduce the cost of the tags, as well as to reduce the size of the electronics as much as possible so as to: (1) increase the yield of the number of chips (dies) that may be produced from a semiconductor wafer, (2) reduce the potential for damage, as the final device size is smaller, and (3) increase the amount of flexibility in deployment, as the reduced amount of space needed to provide the same functionality may be used to provide more capability.
However, as the chips become smaller, their interconnection with other device components, e.g., antennas, becomes more difficult. Thus, to interconnect the relatively small contact pads on the chips to the antennas, intermediate structures variously referred to as “straps,” “interposers,” and “carriers” are sometimes used to facilitate inlay manufacture. Interposers include conductive leads or pads that are electrically coupled to the contact pads of the chips for coupling to the antennas. These leads provide a larger effective electrical contact area between the chips and the antenna than do the contact pads of the chip alone. Otherwise, an antenna and a chip would have to be more precisely aligned with each other for direct placement of the chip on the antenna without the use of such strap. The larger contact area provided by the strap reduces the accuracy required for placement of the chips during manufacture while still providing effective electrical connection between the chip and the antenna. However, the accurate placement and mounting of the dies on straps and interposers still provide serious obstacles for high speed manufacturing of RFID tags and labels.
One such challenging area arises from the fact that the various elements that are assembled to form a complete RFID device are provided arranged on linear arrays such as on a tape or web. The two webs are unwound at matched speeds so that each pair of articles to be assembled reach the assembly point at the same instant, where they are assembled together (e.g. via application of heat, pressure, adhesives, solder, mechanical fasteners, any combination of the foregoing, etc.) For purposes of increasing efficiency, the pitch of these articles (i.e. spacing between them) on the substrate is typically as close as practicable. In the case of antennas and straps, however, because of their different physical size and their respective manufacturing processes as well as subsequent assembly steps for the final product, the pitch of the arrays of the antennas and of the straps on their respective substrates is different. Thus registering (i.e. matching) a strap array with an antenna array is a rather difficult task. Current solutions to this problem include cutting each individual strap and accelerating it to meet the respective antenna at the point of assembly, or unwinding the two webs at different speeds. As those skilled in the art will appreciate, both of these solutions require sophisticated equipment and are prone to encounter problems as the assembly speed is increased.
What is therefore needed are simpler and more economical methods and devices for assembling together articles that are delivered in linear arrays arranged on substrates at different pitches, and which will support high speed assembly of the articles. The embodiments of the present disclosure answer these and other needs.